Billings, M. (2019). Structural Geology (8th.). Pearson.
Lua i Stíl Chicago (17ú heag.)Billings, Marland. Structural Geology. 8th. New Delhi: Pearson, 2019.
Lua MLA (9ú heag.)Billings, Marland. Structural Geology. 8th. Pearson, 2019.
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